要實現手指在螢幕上左右滑動的事件需要例項化物件GestureDetector，new GestureDetector(MainActivity.this,onGestureListener);首先實現監聽物件GestureDetector.OnGestureListener，根據x或y軸前後變化座標來判斷是左滑動還是右滑動並根據不同手勢滑動做出事件處理doResult（int action），

然後覆寫onTouchEvent方法，在onTouchEvent方法中將event物件傳給gestureDetector.onTouchEvent(event);處理。

MainActivity.java

import android.view.GestureDetector;

public class MainActivity extends TabActivity implements OnClickListener {

	final int RIGHT = 0;
	final int LEFT = 1;
	private GestureDetector gestureDetector;

	/** Called when the activity is first created. */
	@Override
	public void onCreate(Bundle savedInstanceState) {
		requestWindowFeature(Window.FEATURE_NO_TITLE);
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);

		gestureDetector = new GestureDetector(MainActivity.this,onGestureListener);
	}

	private GestureDetector.OnGestureListener onGestureListener = 
		new GestureDetector.SimpleOnGestureListener() {
		@Override
		public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
				float velocityY) {
			float x = e2.getX() - e1.getX();
			float y = e2.getY() - e1.getY();

			if (x > 0) {
				doResult(RIGHT);
			} else if (x < 0) {
				doResult(LEFT);
			}
			return true;
		}
	};

	public boolean onTouchEvent(MotionEvent event) {
		return gestureDetector.onTouchEvent(event);
	}

	public void doResult(int action) {

		switch (action) {
		case RIGHT:
			System.out.println("go right");
			break;

		case LEFT:
			System.out.println("go left");
			break;

		}
	}
}